A starting system for a small-sized engine is described which achieves downsizing, light-weight, and cost reduction of the system, prevents entry of dust or foreign substances at the time of assembly, and achieves easy assembly of a motor. The starting system for a small-sized engine includes a recoil starting system and a motor starting system integrated in a starter case, in which the motor starting system has a configuration in which a pinion is mounted on an output shaft of a reducer motor by an one-way clutch of a needle bearing and the pinion is engaged with a starting gear 6 of an engine, and the starter case has a configuration in which an inner lid is secured to a crankcase of the engine together by a screw and the inner lid has a joint portion with respect to the crankcase and a mounting seat for the reducer motor on the outside thereof.